An 8‐year retrospective study of fixed prosthodontics clinical unit completions in a postgraduate prosthodontics program

Abstract Background and Aims The range of aesthetic fixed prosthodontics materials utilizing digital manufacturing techniques has expanded in recent years ostensibly replacing traditional laboratory techniques and materials. This retrospective study conducted over eight consecutive years aimed to analyze the types of laboratory fabricated fixed prosthodontics clinical units completed in a postgraduate prosthodontics specialist training program and determine meaningful trends. Methods The logbooks of eight postgraduate prosthodontics completions from 2014 to 2021 were reviewed and the different types of laboratory fabricated fixed prosthodontics units and total number of fixed prosthodontics units completed were recorded. The data was categorized and presented in tabulated and chart form using Microsoft Excel software (version 2016). Paired t‐tests and Mann−Kendall trend tests were performed to analyze for statistical significance between the different restoration types across the program completions. Results Porcelain bonded to metal (PBM) crowns represented 42.05% of all fixed prosthodontics units completed over all study years followed by all‐ceramic crowns (ACC) (18.14%) and full gold crowns (FGC) (10.70%). Jointly, PBM, ACC and FGC's encompassed 70.88% of all fixed prosthodontics units. Over the 8‐year study period, there were observed trends of reduced use of PBM's, increased use of ACC's, statistically significant reduced use of FGC's (p = 0.035) and a statistically significant difference in the use of complete and partial coverage restorations (p < 0.001). Conclusion PBM crowns were the dominant laboratory fabricated fixed prosthodontic clinical unit across postgraduate prosthodontics program completions. The trend in later years indicating ACC as the dominant crown type warrants further investigation.


| INTRODUCTION
Prosthodontics is the dental specialty pertaining to the diagnosis, treatment planning, rehabilitation and maintenance of the oral function, comfort, appearance and health of patients with clinical conditions associated with missing or deficient teeth and/or maxillofacial tissues using biocompatible substitutes. 1 The training of prosthodontists serves to supply appropriate numbers of practitioners in a niche specialty that deals with complex dental cases such as oral rehabilitations and managing refractory patients.
The postgraduate prosthodontics program at this institution comprises a 3-year, full time training program leading to qualification as a specialist prosthodontist. The program undergoes accreditation every 5 years and aligns with the competencies expected of a graduate specialist in the discipline. 2 The program comprises a mix of clinical treatment; didactic, clinical and case presentation seminars; and a major research project. The clinical component involves the provision of treatment for patients referred to the specialist prosthodontic unit which operates within a public sector specialist dental clinic. All patients are initially assessed by general dentists then referred to the specialist clinic according to the level of complexity of their treatment. Patients are required to be eligible for treatment in the public health care system and make financial copayments that varies according to the clinical procedure.
The university enrolled postgraduate students hold the title of "registrar" in reference to their conjoint employment status within the public sector health service. Throughout the program, the postgraduate registrars receive continual feedback and regular formative review of their work. Summative assessments are conducted at the end of each semester/year and involves presentation of selected clinical cases and submission of a logbook of completed cases that evidence the range of clinical cases managed with emphasis on quality and reflection rather than achieving set quotas.
Assessment of performance in postgraduate/postdoctorate dental specialist training programs is generally a process intrinsic to the university and referenced against required competencies; there are no known reports on this topic in the literature to date. In the US, Board examinations are conducted after graduation that serve to equilibrate the standard of the graduating prosthodontist, however these examinations are not compulsory to practice clinically as a specialist prosthodontist.
Some reports have examined program entry processes 3 with the proposed introduction of national qualifying exams to evaluate applicants for entering programs. 4 Other reports have investigated students' perceptions of prosthodontics and the motivation for entering the specialty with enjoyment found to be the most important factor. 5 However, all such information gaining processes are separate to assessments of students during their course of study.
Fixed prosthodontics is one of the five subdisciplines in the postgraduate prosthodontics program. Prosthodontists are required to remain at the forefront of clinical techniques and have a detailed knowledge of traditional, modern and unusual types of crown materials that often form a key part of specialist referrals and treatments. The use of novel digital manufacturing techniques associated with more efficient, accurate and repeatable results is fundamental to this knowledge, with such technologies recently introduced at this institution. 6,7 Although most registrars entering postgraduate prosthodontics programs have good general dentistry clinical experience, preclinical courses can to some extent introduce postgraduate registrars to specialist level subdiscipline of fixed prosthodontics. At an undergraduate level, fixed prosthodontics preclinical grades have been positively correlated with clinical grades in operative dentistry and fixed prosthodontics 8,9 however it is clinical practice that forms the core in postgraduate prosthodontics programs.
Unit completions can be used as one measure of student progress. 10 Postgraduate prosthodontics registrars maintain a logbook that chronicles unit completions using the accepted schedule describing the different units. 11 There is no limit on the scope of treatment and generally in this